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Related papers: Time Fisher Information associated with Fluctuatio…

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It is shown that, in the framework of non-relativistic quantum mechanics, any conserved Hermitian operator (which may depend explicitly on the time) is the generator of a one-parameter group of unitary symmetries of the Hamiltonian and…

Quantum Physics · Physics 2015-10-19 G. F. Torres del Castillo , J. E. Herrera Flores

This work discusses a variational approach to determining the time evolution operator. We directly see a glimpse of how a generalization of the quantum geometric tensor for unitary operators plays a central role in parameter evolution. We…

Quantum Physics · Physics 2025-04-15 Michael Vogl

We propose a scheme to deal with certain time-dependent non-Hermitian Hamiltonian operators $H(t)$ that generate a real phase in their time-evolution. This involves the use of invariant operators $I_{PH}(t)$ that are pseudo-Hermitian with…

Quantum Physics · Physics 2017-06-19 Boubakeur Khantoul , A. Bounames , M. Maamache

We introduce a positive Hermitian operator, the Fisher operator, and use it to examine a measurement process incorporating unitary dynamics and complete measurements. We develop the idea of information complement, the minimization of which…

Quantum Physics · Physics 2009-02-20 Gabriel A. Durkin

A non-Hermitian operator $H$ defined in a Hilbert space with inner product $\langle\cdot|\cdot\rangle$ may serve as the Hamiltonian for a unitary quantum system, if it is $\eta$-pseudo-Hermitian for a metric operator (positive-definite…

Quantum Physics · Physics 2020-06-05 Ali Mostafazadeh

While fundamental physically realistic Hamiltonians should be invariant under time reversal, time asymmetric Hamiltonians can occur as mathematical possibilities or effective Hamiltonians. Here, we study conditions under which…

Quantum Physics · Physics 2019-08-01 Julian Schmidt , Roderich Tumulka

Fisher Information (FI) is a quantity ubiquitously measured in such varied areas like metrology, machine learning, and biological complexity. Mathematically, it represents a lower bound in the variance of unknown parameters that are related…

Statistical Mechanics · Physics 2026-01-21 Pedro B. Melo , Sílvio M. Duarte Queirós , Diogo O. Soares-Pinto , Welles A. M. Morgado

The quantum measurement axiom dictates that physical observables and in particular the Hamiltonian must be diagonalizable and have a real spectrum. For a time-independent Hamiltonian (with a discrete spectrum) these conditions ensure the…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

Time operator is studied on the basis of field quantization, where the difficulty stemming from Pauli's theorem is circumvented by borrowing ideas from the covariant quantization of the bosonic string, i.e., one can remove the negative…

Quantum Physics · Physics 2015-06-05 Zhi-Yong Wang , Qi Qiu , Cai-Dong Xiong

To admit a canonically conjugate time operator, the Hamiltonian has to be a generator of translations (like the momentum operator generates translations in space), so its spectrum must be unbounded. But the Hamiltonian governing our world…

Quantum Physics · Physics 2024-09-02 Ovidiu Cristinel Stoica

We show that Grover's algorithm defines a geodesic in quantum Hilbert space with the Fubini-Study metric. From statistical point of view Grover's algorithm is characterized by constant Fisher's function. Quantum algorithms changing…

Quantum Physics · Physics 2007-05-23 J. J. Alvarez , C. Gomez

The problem of time in quantum mechanics concerns the fact that in the Schr\"odinger equation time is a parameter, not an operator. Pauli's objection to a time-energy uncertainty relation analogue to the position-momentum one, conjectured…

Quantum Physics · Physics 2017-04-05 M. Bauer

W. Pauli pointed out that the existence of a self-adjoint time operator is incompatible with the semibounded character of the Hamiltonian spectrum. As a result, people have been arguing a lot about the time-energy uncertainty relation and…

Quantum Physics · Physics 2008-11-26 Z. Y. Wang , B. Chen

In this work we intend to study a class of time-dependent quantum systems with non-Hermitian Hamiltonians, particularly those whose Hermitian counterpart are important for the comprehension of posed problems in quantum optics and quantum…

Quantum Physics · Physics 2007-05-23 A. de Souza Dutra , M. B. Hott , V. G. C. S dos Santos

Recent advancements have revealed new links between information geometry and classical stochastic thermodynamics, particularly through the Fisher information (FI) with respect to time. Recognizing the non-uniqueness of the quantum Fisher…

Quantum Physics · Physics 2025-10-07 Laetitia P. Bettmann , John Goold

The existence of a hermitian time operator is proposed in the framework of non-relativistic quantum mechanics.The Heisenberg equation of motion is shown to yield constant rate of flow of time.It is shown to yield results consistent with…

Quantum Physics · Physics 2015-07-21 Carringtone Kinyanjui , Dismas Simiyu Wamalwa

Quantum Fisher information is a key concept in the field of quantum metrology, which aims to enhance the parameter accuracy by using quantum resources. In this paper, utilizing a representation of quantum Fisher information for a general…

Quantum Physics · Physics 2015-07-14 Xiao-Xing Jing , Jing Liu , Heng-Na Xiong , Xiaoguang Wang

Conserved quantities are crucial in quantum physics. Here we discuss a general scenario of Hamiltonians. All the Hamiltonians within this scenario share a common conserved quantity form. For unitary parametrization processes, the…

Quantum Physics · Physics 2015-06-03 Jing Liu , Jing Cheng , Li-Bin Fu , Xiaoguang Wang

We consider dynamics of a quantum scalar field, minimally coupled to classical gravity, in the near-horizon region of a Schwarzschild black-hole. It is described by a static Klein-Gordon operator which in the near-horizon region reduces to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Martinis , V. Mikuta-Martinis

The self adjoint operator of time in non-relativistic quantum mechanics is found within the approach where the ordinary Hamiltonian is not taken to be conjugate to time. The operator version of the reexpressed Liouville equation with the…

Quantum Physics · Physics 2011-11-03 Slobodan Prvanovic